Five Fatal Flaws of Solar Energy

The sun is the most important energy source on Earth. It provides our daily warmth and light and the rotation and orbit of the earth turn its steady output into fluctuating day and night, summer and winter. Solar energy powers the growth of all trees, grasses, herbs, crops and algae; it creates the clouds and powers the storms; it is the source of all hydro, photo-voltaic (PV), solar-thermal, bio-mass and wind energy; and, over geological time, it also creates coal.

PV solar panels are useful in remote locations, for some portable applications and, with enough panels and batteries, stand-alone solar can even power homes.

But solar energy has five fatal flaws for supplying 24/7 grid power.

Firstly, sunshine at any spot is always intermittent and often unreliable. Solar panels can only deliver significant energy from 9am to 3pm – a maximum of 25% of each day. Solar can often help supply the hot afternoon demand for air conditioning, but demand for electricity generally peaks at about 6.30pm, when production from solar is usually zero.

Secondly, to be a stand-alone energy supplier, PV solar needs batteries to cover those times when solar is not producing – about 75% of the time under ideal cloudless skies. To charge the batteries for continuous power, while also supplying usable power, a solar plant can only deliver a theoretical maximum of 25% of its day-time capacity. The chance of cloudy days will greatly increase the battery storage needed, and the generating capacity absorbed in charging the batteries. Currently, only pumped hydro storage could possibly supply the storage capacity needed and then only at massive cost, in a few suitable locations.

Thirdly, solar energy is very dilute, so huge areas of land are needed to collect industrial quantities of energy.

If it were possible to anchor a solar collector one meter square at the top of the atmosphere, aligned continuously to face the sun, and never shadowed by the earth or the moon, it would receive solar energy at the rate of 1,366 Watts per square metre (W/m2) – that would power 13 light bulbs each using 100 watts.

If that panel were located on the surface, at the equator, under clear skies, aligned continuously to face the sun, and never shaded by the earth or the moon, solar energy dissipated by the atmosphere would reduce energy received to 1,000 watts.

In the real rotating world, where sunshine only reaches usable intensity for about 25% of the time, the best located panel would have a capacity factor of about 17% – it would receive 170 watts of energy – not quite 2 light bulbs.

PV solar panels convert solar energy to electrical energy at an efficiency factor of about 15%. Thus our panel, at the equator, year round, should deliver 25.5 watts of electrical energy – one very dim light bulb.

Shift that panel to Melbourne, add clouds, shading, urban air pollution and dirt on the panels, and fix it to a sloping roof often aligned poorly to collect sunshine, and it is time to start the diesel generator in the car port.

It is sensible to use unused space like roofs for solar collectors but such fragmented facilities will never match a compact well-designed solar plant in construction, maintenance and cleaning costs or go close in achieving the correct panel orientation.

People underestimate the land needed for significant solar collectors. In a learned paper published in 2013, Graham Palmer has produced a credible calculation that it would need a square with 31 km sides, completely filled with PV panels, to collect energy equivalent to Australia’s annual electricity requirements.
Source: http://www.mdpi.com/2071-1050/5/4/1406

To also charge batteries to maintain steady supply from a stand-alone solar facility would require at least four times this area – imagine 3,844 square kilometres of collectors, even if suitable battery technology was available.

In addition, PV panels start to degrade in rain, hail and sunshine from the day they are installed, some panels losing significant capacity in as little as three years. And unless washed regularly, dust and bird poop degrades their performance even quicker. All those sparkies checking panel performance and all those cleaning ladies with mops need access roads – this greatly increases the area needed for industrial solar installations.

The fourth fatal flaw of solar energy is the pernicious effect of the dramatic fluctuations in supply on the reliable and essential parts of the grid. When solar electricity floods the network around mid-day, the back-up stations have to throttle back, all the stations needed for stability and backup have their profits reduced, and some may be forced to close, making the network even more fragile and prone to blackouts. Then if a cloud floats across the sky, the backups have to re-start swiftly.

Fifthly, large-scale solar power will create environmental damage over large areas of land. Solar collectors may only manage to convert about 10% of the sun’s energy into electricity, the rest being reflected or turned into heat. But the whole solar spectrum is blocked, thus robbing 100% of the life-giving sunshine from the ground underneath, creating a man-made solar desert. For solar thermal, where mirrors focus intense solar heat to generate steam, birds that fly through the heat beams get fried. Why would true environmentalists support industrial-scale solar energy collection?

All consumers should be free to use solar energy in their own way at their own cost. But these five fatal flaws mean that collecting solar energy will never play more than a minor and very expensive role in supplying grid power.

Desertec, the utopian US$560 billion project designed to cover 16,800 square km of the Sahara Desert with solar panels, and then export electricity 1,600 km to Europe, has collapsed.

A similar fate awaits other attempts to extract 24/7 grid power from intermittent, unpredictable and dilute solar power.

The latest “Desertec Idea” is “solar roads” where highways are paved with solar panels. Imagine the construction and maintenance costs, the length of transmission lines, and the problems of shading and abrasion by traffic, the hazards of cleaning and the random non-ideal orientation of the panels.

Viv Forbes is a geologist , financial analyst and farmer with a degree in Applied Science (geology, physics, chemistry and maths). Since graduation he has studied economics, politics, climatology, soil science, financial analysis, grazing management, hydrology and animal nutrition. He has worked for government departments, private companies and his own business. He has written widely on political, technical and economic subjects. He was awarded the “Australian Adam Smith Award for Services to the Free Society” in 1988, and was chosen as Friedrich Naumann Foundation's "Author of Freedom" in September 2012. He should be retired but is a non-executive director of a small Australian coal exploration company and lives with his wife Judy on their sheep and cattle breeding property at Rosevale in Queensland, Australia. He was the founder of the Carbon Sense Coalition.

It’s not clear to me why solar power generation is being attacked for not being able to do something which nobody ever expected it to do (provide power when the sun isn’t shining). That’s a big “DUH”! What it can do is provide a significant amount of power to offset grid inputs during the middle of the day. The cost is at or approaching grid parity in many areas where grid power is high-cost. In South Australia, rooftop solar panels provided 3.7% of the annual electric energy production in 2012-13; this is predicted to increase to ~8.9% by 2022-2023 (South Australian Electricity Report, 2013), in what seems to me a very conservative scenario. In Germany, solar power is now contributing more than 50% of total power during sunny days. And this contradicts, I think, the statement above that “solar energy will never play more than a minor and very expensive role in supplying grid power.” It’s already playing a significant role, and that’s increasing at a decent rate.

Robert Howd

It’s not clear to me why solar power generation is being attacked for not being able to do something which nobody ever expected it to do (provide power when the sun isn’t shining). That’s a big “DUH”! What it can do is provide a significant amount of power to offset grid inputs during the middle of the day. The cost is at or approaching grid parity in many areas where grid power is high-cost. In South Australia, rooftop solar panels provided 3.7% of the annual electric energy production in 2012-13; this is predicted to increase to ~8.9% by 2022-2023 (South Australian Electricity Report, 2013), in what seems to me a very conservative scenario. In Germany, solar power is now contributing more than 50% of total power during sunny days. And this contradicts, I think, the statement above that “solar energy will never play more than a minor and very expensive role in supplying grid power.” It’s already playing a significant role, and that’s increasing at a decent rate.

Gregory Coyote

One example of a non-tree hugger who has come to a different conclusion about the value of solar energy.
“Furthermore, in the past decade, the United States has lost more than a thousand service members to attacks on convoys primarily hauling fuel that in many instances solar cells can displace since one-third of that fuel is used to generate electricity, as Major General Anthony Jackson points out. “For every fifty trucks carrying fuel,” the general explains, “someone is killed or loses a limb. I know the cost of oil, I know it up front and personal. If you have never seen the mixture of blood and sand, it’s a harsh purple on the desert floor.””http://cleantechnica.com/2014/07/25/dark-side-solar-energy-weaponry/

glb2

As soon as the US government claims ownership of sunlight and sells leases to large corporations, solar will be everywhere. And we’ll be charged by the photon. And taxed by the photon to subsidize the corporations.

liuping

170 watts can run more than 2 light bulbs. Are you still using incandescent bulbs or something something? LED bulbs are 10 watts or less, so that single panels could run 17 light bulbs 24 hours a day. or it could run your computer and monitor all day (assuming you are not using an old CRT monitor and a monster tower PC)

Robert Howd

Yes, liuping, I think you’ve hit on a salient point. It appears that Viv Forbes is from an earlier era, who doesn’t know about LED or even fluorescent bulbs. It might also be relevant to point out that he is a long-time climate change denier, and had this to say about the hazards of smoking: “there is a growing body of evidence which questions the whole statistical basis of the health hysteria surrounding smoking….” (Still posted proudly on his website.) I think it’s time to move on….

Not with Viv Forbes money thanks. What about yours? You will have to pay either way. But what you buy is up to you.

And for those that got here on accident, this is the Heartland Institute echo chamber. Yellow Journalism.

http://www.sheldonthinks.com/ Andrew Sheldon

There is a lot of value in your argument…but the point about land area is not a ‘sales point’. Australia is filled with roads. The fact that they take up a lot of area is not a significant point. I don’t think we should be intimidated by the fact that solar takes 31km2. I also think it might be construed as a straw argument to consider solar as the only option. Understandably, you don’t want to finance poor energy investments. Hopefully, we should see cost effective solar solutions, higher efficiencies as corporations drive absorbed spectra up, capturing a wider range of wavelengths.

David Howes

How’s this for numbers: every two years, the number of watts of electricity produced by solar power doubles. This has been happening for last 75 years. Since 1976, the cost of one watt of solar power has dropped by two orders of magnitude. Graphene will give us better panels and better batteries. This will lead to further drop in costs and prices.

terry1956

flaws yes but not fatal.
The problem is PVs are not cheap enough yet, if they get down to less than 15cents a watt those flaws tend to leave.
If a household could set up a 100 K array including batteries, including back up generation( natural gas, propane, diesel, gasoline, wood, waste cardboard local coal, on site hydro, wind, geothermal, hydrogen, ethanol, methanol, swamp gas) and inverters for say 25,000 2014 federal reserve dollars tens of millions could either go off grid or very seldom use the grid.
I agree utilities should not be forced to load up or buy from the producers and should actually be allowed to demand that producers they don’t want supplying the utility put preventive measure in place not to up load power to the grid.
Household Independence options are very important and local neighborhood independence options are very important to national security.
The NRC needs to also stop dragging its feet on the approval of the small scale Toshiba type buried nuclear reactors that could be set up in neighborhoods and mid size factories or office complexes.
DOD needs to also take another look at small scale Thorium molten salt reactors,, other decentralized energy sources and fusion via paying for results not grants and either open or low bid contracts.